Interlayer decoupling is crucial for achieving unique properties in atomically thin materials, but its application in bulk materials is limited. This study constructs a superlattice of alternating NbSe₂ and highly porous hydroxide layers [(NaOH)_0.5NbSe₂] to demonstrate interlayer decoupling in bulk. Electric decoupling is shown by a 1D insulating state interlayer, while vibrational decoupling is evidenced by the absence of interlayer modes in Raman spectra, dominant local modes in heat capacity, low interlayer coupling energy, and reduced out-of-plane thermal conductivity. This leads to enhanced CDW transition temperature and Pauli-breaking 2D superconductivity, mimicking monolayer NbSe₂ behavior. The findings provide a pathway for large-scale production of materials with intrinsic 2D properties.

Ruijin Sun, Jun Deng, Xiaowei Wu, Munan Hao, Ke Ma, Yuxin Ma, Changchun Zhao, Dezhong Meng, Xiaoyu Ji, Yiyang Ding, Yu Pang, Xin Qian, Ronggui Yang, Guodong Li, Zhilin Li, Linjie Dai, Tianping Ying, Huaizhou Zhao, Shixuan Du, Gang Li, Shifeng Jin, Xiaolong Chen